                   :chs {} ; {ch -> {:id (gen-id), :msgs {msg -> true},
                           ;         :first-taker-actx actx-or-nil}}.
                   :gen-id gen-id})
-            render-ch (chan)
+            delayed-event-ch (chan)
             render-cb (fn [vis-next]
                         (println :on-render-cb @last-id))]
         (reset! prog-world {:world world

                            :clients {}
                            :res-ch (achan-buf world 10)})
        (cbfg.vis/process-events vis event-delay cbfg.vis/vis-event-handlers
                                 event-ch step-ch render-ch)
        (cbfg.vis/process-render el-prefix world render-ch render-cb)
        (make-net world
                  (:net-listen-ch @prog-world)
                  (:net-connect-ch @prog-world))

          (<! prog-ch)
          (close! cmd-ch)
          (close! event-ch)
          (close! delayed-event-ch)
          (recur (inc num-worlds)))))))

; --------------------------------------------
